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1.
Ecol Evol ; 14(2): e10902, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38371862

RESUMO

Exploring the microhabitat determinants of organisms distribution and functional traits differences can help us better understand the importance of intraspecific variations in ecological niches. Investigations on animals functional niche primarily focused on differences among species and tended to neglect the potential variability within species, despite the fact that the ecological and evolutionary importance of intraspecific variations was widely recognized. In this study, we examined the influence of microhabitat features on the intraspecific variability of the distribution and functional traits of a highest elevational distributed lizard species Phrynocephalus erythrurus. To do so, field work was conducted between July and August, 2020 and August and September, 2021 in Namtso watershed in central Xizang, China. Specifically, 11 transects were sampled for P. erythrurus individuals, which were measured for a set of 10 morphological traits. Moreover, 11 microhabitat variables that potentially affect the distribution of lizards were also measured for each transect. Our results indicated that juveniles, males, and females exhibited different functional traits, allowing them to occupy distinct functional space. The distribution of juveniles, males, and females was determined by different microhabitat variables such as illuminance and air temperature. More importantly, these variables also determined the intraspecific functional traits variability in this lizard species. All of these results supported previous claims that intraspecific traits variation should be incorporated into functional ecological studies, and diverse microhabitat features should be conserved to maintain high intraspecific diversity. Future studies can focus on the food analysis to explore the linkage between functional traits and resources utilization within animal populations.

2.
Nat Commun ; 15(1): 1643, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38388555

RESUMO

Implant-associated infections due to the formation of bacterial biofilms pose a serious threat in medical healthcare, which needs effective therapeutic methods. Here, we propose a multifunctional nanoreactor by spatiotemporal ultrasound-driven tandem catalysis to amplify the efficacy of sonodynamic and chemodynamic therapy. By combining piezoelectric barium titanate with polydopamine and copper, the ultrasound-activated piezo-hot carriers transfer easily to copper by polydopamine. It boosts reactive oxygen species production by piezoelectrics, and facilitates the interconversion between Cu2+ and Cu+ to promote hydroxyl radical generation via Cu+ -catalyzed chemodynamic reactions. Finally, the elevated reactive oxygen species cause bacterial membrane structure loosening and DNA damage. Transcriptomics and metabolomics analysis reveal that intracellular copper overload restricts the tricarboxylic acid cycle, promoting bacterial cuproptosis-like death. Therefore, the polyetherketoneketone scaffold engineered with the designed nanoreactor shows excellent antibacterial performance with ultrasound stimulation and promotes angiogenesis and osteogenesis on-demand in vivo.


Assuntos
Antibacterianos , Cobre , Espécies Reativas de Oxigênio , Ultrassonografia , Antibacterianos/farmacologia , Catálise
3.
J Ethnopharmacol ; 323: 117751, 2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38216102

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Qi-Ju-Di-Huang-Pill (QJDH pill) is a Chinese decoction. Although it is commonly used to treat eye conditions, such as diabetic retinopathy (DR), its exact mechanism of action is unknown. AIM OF THE STUDY: To investigate the specific mechanism by which QJDH pill slows the progression of diabetic retinopathy (DR) based on animal and cellular experiments. MATERIAL AND METHODS: The major components of QJDH pill were characterized by ultrahigh-performance liquid chromatography-tandem mass spectrometry (UHPLCMS/MS). C57BL/6J mice were randomly divided into five groups as follows: normal group (control group), model group (STZ group), low-dosage QJDH pill group (QJDH-L group), medium-dosage QJDH pill group (QJDH-M group) and high-dosage QJDH pill group (QJDH-H group). Changes in water intake, urination, food intake, and body mass were monitored weekly, while changes in blood glucose were monitored monthly. Fluorescein fundus angiography (FFA), optical coherence tomography angiography (OCTA), and optical coherence tomography (OCT) were utilized to analyze the changes in fundus imaging indications. Hematoxylin & eosin (H&E) and transmission electron microscopy (TEM) were employed to examine histopathologic and ultrastructural changes in retina. The levels of interleukin-6 (IL-6), interleukin-17 (IL-17), tumor necrosis factor-α (TNF-α), and vascular endothelial growth factor (VEGF) in peripheral blood were detected using Enzyme-linked immunosorbent assay (ELISA). The mouse retina apoptotic cells were labeled with green fluorescence via terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (Tunel). The protein levels of Bcl-2-Associated X (Bax), B cell lymphoma 2 (Bcl-2), Caspase-3, PI3K, phosphorylated PI3K (p-PI3K), protein kinase B (AKT) and phosphorylated AKT (p-AKT) were quantified by Western blot (WB). The retinal pigment epithelium (RPE) cells were cultured and classified into five groups as follows: normal glucose group (NG group), high glucose group (HG group), high glucose + QJDH pill group (HG + QJDH group), high glucose + inhibitor group (HG + LY294002 group), and high glucose + inhibitor + QJDH pill group (HG + LY294002 + QJDH group). Cell viability and apoptosis were detected via Cell Counting Kit-8 (CCK8) and then analyzed by flow cytometry. RESULTS: In vivo experiments revealed that the QJDH pill effectively reduced blood glucose, symptoms of increased water intake, elevated urination, increased food intake and decreased body mass in DR mice. QJDH pill also slowed the development of a series of fundus imaging signs, such as retinal microangiomas, tortuous dilatation of blood vessels, decreased vascular density, and thinning of retinal thickness, downregulated IL-6, IL-17, TNF-α, and VEGF levels in peripheral blood, and inhibited retinal cell apoptosis by activating the PI3K/AKT signaling pathway. Moreover, in vitro experiments showed that high glucose environment inhibited RPE cell viability and activated RPE cell apoptosis pathway. In contrast, lyophilized powder of QJDH pill increased RPE cell viability, protected RPE cells from high glucose-induced damage, and decreased apoptosis of RPE cells by activating the pi3k pathway. CONCLUSION: QJDH pill induces hypoglycemic, anti-inflammatory effects, anti-VEGF and anti-retinal cell apoptosis by activating PI3K/AKT signaling pathway, and thus can protect the retina and slow the DR progression.


Assuntos
Diabetes Mellitus , Retinopatia Diabética , Animais , Camundongos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Retinopatia Diabética/patologia , Interleucina-17 , Fosfatidilinositol 3-Quinases/metabolismo , Interleucina-6 , Fator de Necrose Tumoral alfa/farmacologia , Glicemia , Qi , Camundongos Endogâmicos C57BL , Proteínas Proto-Oncogênicas c-bcl-2 , Apoptose
4.
Small ; : e2309992, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38169093

RESUMO

Transparent dielectric ceramics are splendid candidates for transparent pulse capacitors (TPCs) due to splendid cycle stability and large power density. However, the performance and service life of TPCs at present are threatened by overheating damage caused by dielectric loss. Here, a cooperative optimization strategy of microstructure control and superparaelectric regional regulation is proposed to simultaneously achieve excellent energy storage performance and real-time temperature monitoring function in NaNbO3 -based ceramics. By introducing aliovalent ions and oxides with large bandgap energy, the size of polar nanoregions is continuously reduced. Due to the combined effect of increased relaxor behavior and fine grains, excellent comprehensive performances are obtained through doping appropriate amounts of Bi, Yb, Tm, and Zr, Ta, Hf in A- and B-sites of the NaNbO3 matrix, including recoverable energy storage density (5.39 J cm-3 ), extremely high energy storage efficiency (91.97%), ultra-fast discharge time (29 ns), and superior optical transmittance (≈47.5% at 736 nm). Additionally, the phenomenon of abnormal fluorescent negative thermal expansion is realized due to activation mechanism of surface phonon at high temperatures that can promote the formation of [Yb···O]-Tm3+ pairs, showing great potential in real-time temperature monitoring of TPCs. This research provides ideas for developing electronic devices with multiple functionalities.

5.
ACS Appl Mater Interfaces ; 16(5): 5977-5988, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38266025

RESUMO

Previous bismuth-based photocatalysts usually employ a strong acid solution (e.g., HNO3 solution) to obtain an ultrathin structure toward high photocatalytic activity. In this work, the ultrathin layered BiOIO3 nanosheets are successfully synthesized using just the glucose hydrothermal solution. The high-concentration glucose solution shows the obvious acidity after the hydrothermal process, which leads to the quick decrease in thickness of BiOIO3 nanosheets from ∼45.58 to ∼5.74 nm. The ultrathin structure can greatly improve charge carriers' separation and transfer efficiency. The generation of reductive iodide ions brings about oxygen vacancies in the ultrathin nanosheets, then the defect energy level is formed, causing the decreased band gap and improving the visible light absorption. Compared to thick BiOIO3 nanosheet with little oxygen vacancies, much higher carrier separation efficiency and visible light absorption are achieved in the ultrathin nanosheets with oxygen vacancies, resulting in an excellent photocatalytic performance (0.1980 min-1 for RhB degradation), which is much higher than most other bismuth-based photocatalysts. The superoxide radicals (•O2-) and holes (h+) are the major active species responsible for high photocatalytic activity. This work affords an environmentally friendly strategy to synthesize ultrathin photocatalysts with superior photocatalytic properties.

6.
Phytochemistry ; 217: 113920, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37951561

RESUMO

Ten lignans, including six previously undescribed phenolic ester glycosyl lignans (1-6), were isolated from a well-known traditional Chinese medicine, Qin-Jiao, which is the dry root of Gentiana macrophylla Pall. (Gentianaceae). Their structures were determined by spectroscopic and chemical methods, especially 2D NMR techniques. Quantum chemical calculations of theoretical ECD spectra allowed the determination of their absolute configurations. Refer to its traditional applications for the treatment of rheumatic arthralgia and hepatopathy, these compounds were evaluated on a TNF-α induced MH7A human synoviocyte inflammation model and a D-GalN induced AML12 hepatocyte injury model. Compounds 1, 2, 5, and 6 significantly reduced the release of proinflammatory cytokine IL-1ß in MH7A cells at 15 µM and they also could strongly protect AML12 cells against D-GalN injury at 30 µM. Flow cytometry and Western blot analysis showed that compound 5 ameliorated D-GalN induced AML12 cell apoptosis by upregulating the expression of anti-apoptotic Bcl-2 protein and down-regulating the expression of pro-apoptotic Bax protein.


Assuntos
Medicamentos de Ervas Chinesas , Gentiana , Lignanas , Humanos , Gentiana/química , Lignanas/farmacologia , Glucosídeos/farmacologia , Glucosídeos/química , Medicamentos de Ervas Chinesas/farmacologia , Inflamação
7.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 54(5): 923-929, 2023 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-37866947

RESUMO

Objective: In recent years, due to the development of accelerated recovery after surgery and day surgery in the field of surgery, the average length-of-stay of patients has been shortened and patients stay at home for post-surgical recovery and healing of the surgical incisions. In order to identify, in a timely manner, the problems that may appear at the incision site and help patients prevent or reduce the anxiety they may experience after discharge, we used deep learning method in this study to classify the features of common complications of surgical incisions, hoping to realize patient-directed early identification of complications common to surgical incisions. Methods: A total of 1 224 postoperative photographs of patients' surgical incisions were taken and collected at a tertiary-care hospital between June 2021 and March 2022. The photographs were collated and categorized according to different features of complications of the surgical incisions. Then, the photographs were divided into training, validation, and test sets at the ratio of 8∶1∶1 and 4 types of convolutional neural networks were applied in the training and testing of the models. Results: Through the training of multiple convolutional neural networks and the testing of the model performance on the basis of a test set of 300 surgical incision images, the average accuracy of the four ResNet classification network models, SE-ResNet101, ResNet50, ResNet101, and SE-ResNet50, for surgical incision classification was 0.941, 0.903, 0.896, and 0.918, respectively, the precision was 0.939, 0.898, 0.868, and 0.903, respectively, and the recall rate was 0.930, 0.880, 0.850, and 0.894, respectively, with the SE-Resnet101 network model showing the highest average accuracy of 0.941 for incision feature classification. Conclusion: Through the combined use of deep learning technology and images of surgical incisions, problematic features of surgical incisions can be effectively identified by examining surgical incision images. It is expected that patients will eventually be able to perform self-examination of surgical incisions on smart terminals.


Assuntos
Aprendizado Profundo , Ferida Cirúrgica , Humanos , Ansiedade , Transtornos de Ansiedade , Período Pós-Operatório
8.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 54(4): 759-764, 2023 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-37545070

RESUMO

Objective: To construct a risk predictive model for postoperative sleep disturbance (PSD) in patients undergoing arthroplasty by using logistic regression. Methods: We retrospectively collected the data of 4286 patients who underwent joint replacement surgeries at a tertiary-care hospital in Chengdu, China between January 1, 2017 and September 30, 2021. With 3001 cases in the training set and 1285 cases in the test set, we constructed the model by using a logistic regression algorithm to screen for predictors in Matlab, displaying the predicted risks of postoperative sleep disturbance with nomographs. The performance of the model was assessed by the area under the curve ( AUC) of the receiver operating characteristic curve, accuracy, precision, recall, F1 value, and calibration curve. Results: A total of 9 predictors, including post-admission preoperative sleep disturbance, ward type, body mass index, smoking status, range of diseases, joint mobility (flexion), joint mobility (extension), preoperative last hemoglobin, and type of surgery, were eventually included in the study for predictive modeling . The performance assessment findings of the predictive model were as follows, AUC value, 0.708 (95% confidence interval: 0.677-0.740), accuracy, 75.20%, precision, 65.80%, recall, 43.70%, and F1 value, 0.525. The calibration curve showed good agreement between the predicted probabilities and the actual data. Conclusion: The model constructed in the study has good predictive efficacy and the nomographs are simple and easy to use. With this model, health workers can make preoperative prediction of the risk of PSD in arthroplasty patients based on the predictors, which facilitates early prevention and reduces the risk of postoperative sleep disturbance in patients.


Assuntos
Artroplastia , Sono , Humanos , Estudos Retrospectivos , Modelos Logísticos , Curva ROC
9.
BMJ Paediatr Open ; 7(1)2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37407249

RESUMO

BACKGROUND: Autism spectrum disorder (ASD) is a diverse neurodevelopmental disease primarily distinguished by limited and stereotyped activities as well as impaired social interaction. Due to the high heritability of ASD, research on the disorder has emphasised on identifying the underlying genetic and epigenetic aetiology. Many ASD loci have been identified by genome-wide association studies (GWASs). However, GWASs are more susceptible to bias due to population stratification. Moreover, GWASs barely reflect the genetic aetiology of subtypes of behavioural deficits. METHODS: We applied whole-genome transmission disequilibrium test (TDT) to reveal the gene sets that are significantly associated with the four behavioural subtypes of restricted repetitive behaviours in 334 ASD trios. We further mapped the clustered genes to pathways and enriched the SFARI genes in these pathways. RESULTS: Four unique gene clusters (181 genes in total) that are related to four different behavioural subtypes in ASD were identified. 23 SFARI genes were enriched in these four clusters. Through pathway analysis, nine non-SFARI genes (CNDP1, ETNK1, ITPKB, KCNQ5, PDE4D, PDGFRA, PPARGC1A, ULK2, SYNJ2) were found to be linked to the SFARI genes, which may contribute to the development of ASD. Furthermore, we found that the mTOR pathway enriched with the CNDP1, PDE4D, ULK2 genes is associated with neurodevelopment. CONCLUSIONS: Whole-genome TDT test is a unique tool in clustering genes related to ASD subtypes of behavioural deficits. Several new candidate genes for ASD are revealed by pathway analysis of the clustered genes. These findings are useful for understanding the underlying mechanism of ASD.


Assuntos
Transtorno do Espectro Autista , Deficiência Intelectual , Humanos , Transtorno do Espectro Autista/genética , Transtorno do Espectro Autista/epidemiologia , Estudo de Associação Genômica Ampla , Deficiência Intelectual/genética , Família Multigênica/genética
10.
Chemosphere ; 338: 139548, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37467862

RESUMO

The decaying photocatalytic rate caused by carrier recombination is a thorny problem that has not been properly solved. Improvement of photocatalysis can be achieved through structural innovation, diversification of catalytic modes, or a combination of both. Herein, effective separation of photo-generated carriers in Bi0·5Na0·5TiO3/ZnO composites was achieved by heterojunction construction for energy band regulation and synchronously mechanical energy harvesting from piezoelectric effect. The formation of heterojunctions between Bi0·5Na0·5TiO3 and ZnO was confirmed by electron microscopy and analysis of X-ray photoelectron spectroscopy spectra. The degradation performance of Rhodamine B, a representative industrial dye contaminant, was optimized through the formation of Bi0·5Na0·5TiO3/ZnO heterojunctions and ultrasonic vibration harvesting. Their band structures were described in detail and electrochemical tests were performed to substantiate a novel Z-scheme heterostructure that can explain the carrier separation and transfer processes in catalysis. The piezoelectric polarization field generated by the piezoelectric effect of both Bi0·5Na0·5TiO3 and ZnO coordinates perfectly with the photocatalysis, enabling the piezo-photocatalysis. Our research opens a promising avenue in alleviating charge carrier complexation through heterojunction construction and mechanical strain for future pollutants degradation via catalysis.

11.
Curr Zool ; 69(2): 121-127, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37091999

RESUMO

Reintroduction of captive-bred Chinese giant salamanders is a primary approach for restoring wild populations. Despite previous studies have investigated the habitat preferences of reintroduced Chinese giant salamanders, the intraspecific variation in their habitat selection has been neglected. In the present study, 30 captive-bred Chinese giant salamanders belonging to 3 groups (i.e., 10 males, 10 females, and 10 juveniles) were released into a montane stream to explore whether intraspecific variation in habitat selection occurred in this species using radiotelemetry. Our results indicated that linear home range and daily movement of males were significantly higher than those of females and juveniles. Male sedentariness was significantly lower than that of females and juveniles. No significant differences were detected between females and juveniles in these measures. Importantly, we found that males preferred microhabitats with low water conductivity and deep water depth. Females preferred microhabitats with high water conductivity, low dissolved oxygen and ammonium-nitrogen, and slow current velocity, while juveniles occupied microhabitats with low ammonium-nitrogen. In addition, males and juveniles exhibited higher niche breadth than females. Niche overlap was high between adults and juveniles but low between males and females. Our study revealed the presence of spatial segregation in reintroduced Chinese giant salamanders. Males, females, and juveniles exhibited variation in microhabitat selection. These results provide important information for use when planning strategies for conservation of Chinese giant salamanders.

12.
Front Genet ; 14: 1108440, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37035742

RESUMO

Purpose: To establish an effective genomic diagnosis pipeline for children with autism spectrum disorder (ASD) for its genetic etiology and intervention. Methods: A cohort of 354 autism spectrum disorder patients were obtained from Beijing Children's Hospital, Capital Medical University. Peripheral blood samples of the patients were collected for whole genome sequencing (WGS) and RNA sequencing (RNAseq). Sequencing data analyses were performed for mining the single nucleotide variation (SNV), copy number variation (CNV) and structural variation (SV). Sanger sequencing and quantitative PCR were used to verify the positive results. Results: Among 354 patients, 9 cases with pathogenic/likely pathogenic copy number variation and 10 cases with pathogenic/likely pathogenic single nucleotide variations were detected, with a total positive rate of 5.3%. Among these 9 copy number variation cases, 5 were de novo and 4 were inherited. Among the 10 de novo single nucleotide variations, 7 were previously unreported. The pathological de novo mutations account for 4.2% in our cohort. Conclusion: Rare mutations of copy number variations and single nucleotide variations account for a relatively small proportion of autism spectrum disorder children, which can be easily detected by a genomic testing pipeline of combined whole genome sequencing and RNA sequencing. This is important for early etiological diagnosis and precise management of autism spectrum disorder with rare mutations.

13.
RSC Adv ; 13(17): 11720-11727, 2023 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-37063737

RESUMO

As emerging contaminants, antineoplastic drugs are widely used, but their residues in water may cause long-term genotoxicity to aquatic organisms and human beings. Here, waste moxa ash was selected as biomass raw material and modified by ball milling to obtain carbon-based materials with excellent adsorption performance, which were used to remove the antineoplastic drug mitoxantrone (MTX) from water. The experimental results indicate that moxa ash modified by ball milling in hydrogen peroxide exhibits ultrafast removal of MTX (the removal efficiency reaches 97.66% in 1 min and 99.72% in 30 min). The pseudo-second-order kinetics and Freundlich isotherm models accurately describe the MTX adsorption process, and the mechanism of adsorption probably involves pore filling, hydrogen bond, π-π interaction and electrostatic attraction. Not only that, moxa ash also has the ability to remove dyes such as malachite green (97.81%) and methylene blue (99.97%). In this study, a simple and environmentally friendly process was used to convert waste moxa ash into an effective MTX adsorbent, providing a feasible solution for controlling MTX pollution and identifying a circular and economic way to reuse the waste.

14.
Artigo em Inglês | MEDLINE | ID: mdl-36908056

RESUMO

The electric-field-modulation (E-modulation) of photoluminescence (PL) properties in bulk ceramics has attracted tremendous interest due to its potential application in optical data storage and communication devices. One promising approach of reversibly and largely modulating the PL intensity has been proposed in rare-earth Er3+-doped Pb0.96La0.04Zr0.9Ti0.1O3 (PLZT) antiferroelectrics (AFEs) based on the unique E-dependent antiferroelectric-ferroelectric (AFE-FE) phase transition. However, the AFE phase stability of PLZT doped with various Er contents and their E-modulated PL properties have not been systematically investigated. In this paper, the intrinsic AFE phase of PLZT-Er is found to be stabilized in the high-temperature and high-E regions with increasing Er3+ content. The enhanced AFE nature caused by increasing Er doping leads to a larger E-dependent PL tunability (∼35%). Moreover, the ceramics exhibit the characteristics of both upconversion and downconversion PL (UCPL and DCPL) effects. Based on the excellent E-dependent dual-mode PL tunability, an optoelectronic device named the optical latch is demonstrated, where an electric signal can be used to trigger a notable intensity change in both the UCPL and DCPL modes. This reversible E-dependent dual-mode capability in PLZT-Er sheds light on a feasible approach to optoelectronic applications.

15.
ACS Appl Mater Interfaces ; 15(13): 16828-16841, 2023 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-36973872

RESUMO

A combination of transparency and photochromic (PC) properties in ferroelectrics has promising application potential in smart windows and optical storage/imaging. Nonetheless, limited by understanding the underlying PC mechanism, a splendid PC performance is rarely achieved in transparent ferroelectrics. Here, a strategy to construct deep-lying traps by ion-doping induced defect engineering in (K0.5Na0.5)NbO3-based ferroelectric ceramics is proposed. Based on the improved density functional theory simulations, a high concentration of vacancy defects can be realized by codoping 1 mol % Pr and 4 mol % Ba in (K0.5Na0.5)NbO3, which helps achieving deep-lying traps and then superior PC performance. Through traditional pressureless sintering, highly transparent ceramics with designed optimal composition have been fabricated in a wide sintering temperature range (1170-1210 °C), exhibiting an ultrafast PC feature, i.e., 0.1 s response time (by illumination of 400 nm light), along with high PC efficiency (5.8 cm2·W-1) and PC rate (7.1 s-1), preeminent among reported inorganic PC transparent materials. Additionally, the ceramics have been utilized for real-time optical recording, displaying unambiguous patterning with long-time preservation (21 days). This research supplies a paradigm for designing high-performance PC transparent materials in optical applications and helps deepen the comprehensive understanding of the PC mechanism.

16.
Front Zool ; 20(1): 7, 2023 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-36740695

RESUMO

BACKGROUND: Functional diversity is important to maintain ecosystem functioning. Species with different ecomorphological traits may display distinct functional roles in ecosystems. Accordingly, functionally extreme species are more important as they can exhibit specific strategies. However, little is known about the distribution patterns of functionally extreme species at a local scale and whether the prior extinction of extreme species can cause significant effects on functional diversity. In addition, no empirical studies have been conducted on the microhabitat determinants of extreme species to maintain the functional diversity. RESULTS: This study collected 1470 tadpoles belonging to 6 families and 20 anuran species. These species were subsequently divided into 65 functional entities based on their developmental stages to incorporate intraspecific traits variability. As a result, we detected seven extreme functional entities, accounting for 10.7% of the total number of entities. Moreover, the prior extinction of extreme entities can lead to a significant decrease in functional diversity compared with the random extinction of entities. Microhabitat variables such as conductivity, water depth, and current velocity determined the distribution of extreme entities. CONCLUSION: Although the functionally extreme entities only represented a small proportion of the total number of tadpoles, they played irreplaceable roles in maintaining functional diversity. Their extinction may induce high functional vulnerability in tadpole communities. Therefore, anuran species with extreme tadpole traits need to be projected for amphibian conservation.

17.
Sci Total Environ ; 859(Pt 1): 160105, 2023 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-36370793

RESUMO

Declining body size is a universal ecological response to global warming in ectotherms. Ectotherms grow faster but mature at a smaller size at higher temperatures. This phenomenon is known as the temperature-size rule (TSR). However, we know little about the details of the relationship between temperature and size. Here, this issue was studied in the Chinese giant salamander (Andrias davidianus), one of the largest extant amphibians and a flagship species of conservation in China. Warm-acclimated A. davidianus larvae (25 °C) had accelerated development but little superiority in body growth when compared to their 15 °C counterparts when fed with red worm. This predicts a drastic decrease in adult body size with warming. However, a fish diet (more abundant lipid and protein) improved the growth performance at 25 °C. The underlying mechanism was studied. Warm-acclimated larvae had enlarged livers but shortened tails (fat depot). Their livers suffered from energy deficiencies and decreased protein levels, even when protein synthesis and energy metabolism were transcriptionally upregulated. This could be a direct explanation for their poor growth performance. Further analyses revealed a metabolic disorder resembling mammal glycogen storage disease in warm-acclimated larvae, indicating deficiency in glycogen catabolism. This speculation is consistent with their increased lipid and amino acid catabolism and explained the poor energy conditions of the warm-acclimated larvae. Additionally, a deficiency in glycogen metabolism explains the different efficiency of worm and fish diets in supporting the growth of warm-acclimated larvae, even when both diets were provided sufficiently. In conclusion, our results suggest that the relationship between temperature and body size can be flexible, which is a significant finding in terms of the TSR. The underlying metabolic and nutrient mechanisms were revealed. This knowledge can help deepen our understanding of the consequences of warming and can contribute to the conservation of A. davidianus.


Assuntos
Aclimatação , Anfíbios , Animais , Temperatura , Aclimatação/fisiologia , Tamanho Corporal , Urodelos , Larva , Glicogênio , Lipídeos , Mamíferos
18.
Front Microbiol ; 13: 1062604, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36532427

RESUMO

Microorganisms play as fundamental contributors to maintain hosts' fitness, which can be shaped by external environment. Moreover, symbiotic microbiome also varied within species (e.g., between sexes and developmental stages). However, we still need more studies to quantify whether the intraspecific variation patterns of symbiotic microbes can be modified with the change of environment. The Chinese giant salamander (CGS; Andrias davidianus) is a Critically Endangered species. Despite quantitative captive bred individuals were released to rebuild wild populations, the effectiveness is limited. More importantly, no studies have revealed the adaptation of released CGSs to the complex field conditions. In the present study, we explored whether reintroduction can reshape the intraspecific variations of symbiotic microbiota in captive bred CGSs using high-throughput amplicon sequencing of the16S rRNA gene. We found no significant difference of symbiotic microbiome in captive bred males and females, but released males and females differed significantly in skin microbiome. Juveniles had higher diversity of microbial symbiont than adults in hatchery, but lower diversity in field. Moreover, dominant bacterial taxa differed between juveniles and adults in both hatchery and field. Importantly, this symbiotic microbiome variations within species can be modified (alpha and beta diversity, and community composition) when captive bred individuals were released to the field. Overall, we observed a lower alpha diversity and higher relative abundance of Chryseobacterium, Plesiomonas, and Acinetobacter in the bacterial community of captive bred individuals. Instead, higher alpha diversity of symbiotic microbiota and higher relative abundance of S24-7 and Lactobacillus was detected in released individuals. These modifications may associate with the change of living environment, as well as the specific behavior within CGSs (e.g., movement patterns and foraging activities). Future studies can incorporate other approaches (e.g., blood physiology) to better evaluate the growth and health of reintroduced CGSs.

19.
Phys Chem Chem Phys ; 24(45): 27670-27677, 2022 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-36373615

RESUMO

Environmentally friendly potassium sodium niobate (KNN)-based ceramics are potential electronic functional materials due to multiphase coexistence. Aliovalent doping on the A-site with different ions plays a key role in phase boundary engineering. However, the difference of contribution to the phase boundary from various A-site dopants is not clear in multielement high performance KNN-based ceramics. Herein, the individual contribution to phase structure and comparison of typical aliovalent ions (Bi3+ and Ca2+) on the A-site, are considered in terms of influence on electrical properties. Within a maintained rhombohedral-orthorhombic-tetragonal (R-O-T) phase boundary at room temperature, both phase transition temperatures for rhombohedral-orthorhombic (TR-O) and orthorhombic-tetragonal (TO-T) gradually enhance with increasing Ca2+ and decreasing Bi3+, resulting in elevating R phase and reducing T phase. This phenomenon indicates that the contribution of Ca2+ to increase TR-O is stronger than that from Bi3+, while the effect on decreasing TO-T from Ca2+ is weaker with respect to Bi3+ during phase boundary formation. The enhancement of TR-O and TO-T is due to the lower electronegativity of Ca2+ than Bi3+ which benefits an R phase with high ionicity. There is only a small change in TC and diffusion degree when Bi3+ is replaced by Ca2+, because of the similar substitution of Bi3+ and Ca2+ on the A-site. Meanwhile, enhanced O vacancies are due to the lower valence of Ca2+ than that of Bi3+. Then, electrical properties including ferroelectricity, piezoelectricity and strain, retain high values originating from the maintained R-O-T phase boundary. Moreover, improved stability of piezoelectricity and strain under changing temperature, are achieved based on enhanced TO-T. Thus, this work provides an effective method to further optimize multiphase structures via appropriate doping in KNN-based ceramics.

20.
Proc Biol Sci ; 289(1984): 20221394, 2022 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-36196548

RESUMO

Low temperature imposes strong selective pressure on ectotherms. To maximize their overall fitness under cold conditions, the ectotherms may either try to maintain their physiological activities through metabolic compensation or enter into metabolic depression; however, some species adopt both strategies to cope with different degrees of cold. Nevertheless, how these two seemingly opposite strategies are coordinated has rarely been elucidated. Here, we investigated the molecular strategy underlying the cold acclimation of Andrias davidianus, the largest extant amphibian, using multi-organ metabolomics and transcriptomics. The results showed remarkable organ heterogeneity in response to cold. While most organs showed transcriptional upregulation of metabolic processes, the heart exhibited downregulation. This heterogeneity explained the adaptive reorganization in resource allocation, which compensates for metabolic maintenance by compromising growth. Importantly, the cardiac function might constitute a 'ceiling' to constrain the space for compensation, especially under colder conditions. Additionally, the opposite transcriptional regulation of oxidative phosphorylation and other pathways might also shape the overall metabolic capacity under cold conditions. The heterogeneity in cold responses may have directed a shift in cold adaptive strategy from compensation to depression with a drop in temperature. These results provide a novel insight into the regulatory mechanisms underlying cold survival strategies of ectotherms.


Assuntos
Aclimatação , Temperatura Baixa , Aclimatação/fisiologia , Anfíbios , Animais , Metabolômica , Temperatura
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